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Subject: Re: [PATCH v2] rbtree: fix the red root
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Cc: David Lechner <david@lechnology.com>, Michel Lespinasse <walken@google.com>, Andrew Morton <akpm@linux-foundation.org>, "jejb@linux.ibm.com" <jejb@linux.ibm.com>, "martin.petersen@oracle.com" <martin.petersen@oracle.com>, "joeypabalinas@gmail.com" <joeypabalinas@gmail.com>, linux-mm <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>



On 1/14/19 1:23 AM, Esme wrote:
> I did not yet verify the previous branches but did tune out kmemleak (CONFIG_DEBUG_MEMLEAK no longer set) as it seemed a bit obtrusive in this matter, this is what I see now (note redzone?).
> /Esme
> 
>   114.826116] =============================================================================
> [  114.828121] BUG kmalloc-64 (Tainted: G        W        ): Padding overwritten. 0x000000006913c65d-0x000000006e410492
> [  114.830551] -----------------------------------------------------------------------------
> [  114.830551]
> [  114.832755] INFO: Slab 0x0000000054f47c55 objects=19 used=19 fp=0x          (null) flags=0x1fffc0000010200
> [  114.835063] CPU: 0 PID: 6310 Comm: x Tainted: G    B   W         5.0.0-rc2 #15
> [  114.836829] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.1-1ubuntu1 04/01/2014
> [  114.838847] Call Trace:
> [  114.839497]  dump_stack+0x1d8/0x2c6
> [  114.840274]  ? dump_stack_print_info.cold.1+0x20/0x20
> [  114.841402]  slab_err+0xab/0xcf
> [  114.842103]  ? __asan_report_load1_noabort+0x14/0x20
> [  114.843244]  ? memchr_inv+0x2c1/0x330
> [  114.844059]  slab_pad_check.part.50.cold.87+0x27/0x81

Confused again. Those slab_pad_check() looks like only with SLUB, but you said
you used SLAB. What else did you change?